1. Field of the Invention
The present invention relates generally to multi-participant conferencing systems, and more particularly to utilization of local video in an integrated multi-participant conferencing system having a back-channel connection.
2. Description of the Related Art
Conferencing systems generally define the ways in which a set of participants may collaborate. The structures of conferencing systems typically establish the rules for information exchange. Methods of communication are identified and defined, and accessible media is identified within the conferencing system structure. Some systems may allow for communication with remote or mobile participants, while others limit access to dedicated locations or members. Features such as grouping participants into logical meeting spaces, assigning security access rights to a collaboration, specializing in particular types of media communication, and so forth, are all elements of various conferencing systems.
Participants in a videoconference typically receive media from several contributing sources in a collaborative exchange. Such media includes, but is not limited to, video, audio, slide shows, etc., and can be offered by either or both the individual participants in the video conference as well as the conferencing system itself. Looking at just the video portion of the media, participants, whether or not the participant contributes media to the conferencing system, typically receive a single video signal representing a view of the conference.
Depending on the conferencing system used, the conference view displayed to each participant may be divided into regions according to a video layout or presentation chosen by the individual participant or by the conferencing system. Each region displayed may represent participants in the conference, or a single region representing a primary speaker may be selected or defined, or any number of variations of video presentation according to the level of sophistication or complexity of the particular conferencing system and according to preferences of conference participants.
It is often advantageous for a contributing participant in a videoconference to have a view or display of the video that the contributing participant is providing to the collaboration. Such a view or display provides feedback to the contributing participant, allowing the contributing participant to ensure that what is being provided is accurate, desirable, and is conveying the message or view intended (i.e., the subject is in frame, the subject has correct focus and exposure, etc.) In the typical conferencing system, the contributing participant's own video is simply another media in the conference. Consequently, a region in a video presentation or layout may be identified to contain the view of the contributing participant's own video. The result is that the contributing participant sees him or herself in one of the defined regions of the video presentation or layout.
Typically, all video in the videoconference, including the “self video” described above, is sent from a participant using a conference client of the conferencing system to a media mixer of the conferencing system. The conferencing system then returns a video signal according to the participants' selections, including, if selected, the contributing participant's self video. As with many communication systems, the process as described introduces latency through transmission delays and processing time. Additionally, video quality can be diminished as the video signal may be operated on by encoders, decoders, mixers, processors, etc., and is affected by transmission limitations including bandwidth or signal loss. The resulting self video, therefore, is typically degraded, distracting, and generally undesirable.
Some prior art approaches to achieving acceptable self or local video include the providing of local video through a separate loopback technique. In this approach, video from a local camera device is both forwarded to the conferencing system for mixing with all other video, and is displayed directly on the conference client to the contributing participant. Common techniques for the local presentation include display of a separate video window, display in the video presentation or layout as a Picture-In Picture over or within the system video presentation or layout, and the use of a separate local video display. While such techniques benefit the contributing participant by enabling essentially real-time video display, drawbacks include possibly needing more display area, increased window management, more equipment may be required, and the need to monitor more than one display.
In view of the foregoing, what is needed is a videoconferencing system that implements a local video loopback method providing useful video presentation or layout and region interfaces, enhancing the videoconference environment, and that is easily implemented.